From Teflpedia

The letter combination "ua" has several different pronunciations. Normally each vowel is pronounced independently in a separate syllable. See Decoding the letter U and Decoding the letter A.

Do not confuse the second u in consonant digraphs ⟨bu⟩, ⟨cu⟩, ⟨gu⟩, ⟨qu⟩ and ⟨su⟩ as the first vowel of a vowel digraph. The actual number of English words with this digraph is actually small, if there are any.